Optical reflector system

ABSTRACT

An optical reflector system is disclosed utilizing a plurality of reflecting surfaces forming a diverging tunnel to project a substantially uniform intensity on an optical surface spaced from the reflector system. The invention is suitable for use with optical projection systems and is able to compensate for the effects of other optical components within the projection system. The reflector system is applicable to high speed character projection as used in the photo-composition and photo-type setting arts.

sewerage 5R xii 32693951 wzmaoww DHLGEES fa Baker 1 cm I 1 [541 OPTHCALREFLECTOR SYSTEM [72] Charles W. Baker, Cedar Grove,

Varl-typer Corporation, Hanover, NJ.

lnventor:

[73] Assignee:

[22] Filed: 'April30, 1971 [21] App1.No.: 139,112

[52] HS. Cl ..95/4.5 R, 352/203, 353/38 [51] 11nt.Cl ..B4lb 21/08, B4lb21/12 [58] Field oi Search ..95/4.5; 352/198, 203; 350/96 T, 4; 353/38,20; 240/413, 41.4, 106,

[56] References Cited UNITED STATES PATENTS 3,368,198 2/1968 Eikenberryet a1 340/378 X 3,484,599 12/1969 Little ..240/41.3

[ 1 Sept. 26, 1972 2,764,071 Huebner ..95/4.5 R 3,064,545 11/1962Scantlin ..95/4.5 R 1,577,388 3/1926 Twyman ..350/96 T 3,543,657 12/1970Rosenblum ..95/4.5 R 3,509,804 5/1970 Kohler et a1. ..95/4.5 R

Primary ExaminerRobert P. Greiner Att0rneyRusse11 L. .Root and Ray S.Pyle [57] ABSTRACT An optical reflector system is disclosed utilizing aplu;

rality of reflecting surfaces forming a diverging tunnel to project asubstantially uniform intensity on an optical surface spaced from thereflector system. The invention is suitable for use with opticalprojection systems and is able to compensate for the effects of otheroptical components within the projection system. The reflector system isapplicable to high speed character projection as used in thephoto-composition and photo-type setting arts.

25 Claims, 10 Drawing Figures PATENTEUsms x972 SHEET 1 0F 2 @S b/QATTUENEY 1 orrrcsr. anrtncron sYsraM BACKGROUND OF THE INVENTION Thisinvention relates to optical systems and more particularly to opticalreflector systems.

A review of the prior art will disclose a multitude of patents relatingto optical reflector systems. These prior art reflector systems can bedivided into two classes. The first class includes reflector systemshaving curved surfaces. Reflector systems having the shape of thevarious conical sections are examples of this first class of reflectorsystems. The second class of reflector systems is composed of reflectorshaving a plurality of flat reflecting surfaces arranged around a lightsource to project light in a given direction. Flat reflecting surfacesformed in the shape of a straight tunnel are included in this secondclass.

The recent trend in the manufacturing of industrial equipment is towardminiaturization. The first class of reflector systems being composed ofcurved surfaces were in general large and bulky and were not applicableto the miniaturized industrial equipment. Manufacturers more recentlyhave adapted the flat surface reflector systems. A majority of thesesystems were in the form of an optical tunnel having parallel flatreflecting surfaces with light entering one end and propagating from theopposite end of the tunnel. These systems were easier to manufacture andless expensive than the curved surface systems. However, the tunnelslack a balanced combination of diffused and directed light to produce auniform intensity on an optical surface spaced from the tunnel. Finally,the prior art tunnel systems clid not have the ability to compensate forthe effects of other optical components within an optical projectionsystem incorporating the tunnel.

Therefore, an object of this invention is to produce an opticalreflector system which is compact.

Another object of this invention is to produce an optical reflectorsystem which can be produced at a minimum of cost. I

Another object of this invention is to produce an optical reflectorsystem which has the proper combination of diffused and directed light.

Another object of this invention is to produce an optical reflectorsystem which is able to compensate for the effects of other opticalcomponents within an optical projection system.

Another object of this invention is to produce an optical reflectorsystem which can be adapted to a given application.

Another object of this invention an optical reflector system which isreproduceable and interchangeable with similar reflector systems.

Another object of this invention is to produce an optical reflectorsystem in which no adjustment is necessary when placed within machinesduring a manufacturing process.

Another object of this invention is to produce an optical reflectorsystem which projects a substantially uniform intensity beam within theprojected angle.

SUMMARY OF THE INVENTION The invention may be incorporated in an opticalreflector system, comprising in combination, a first and a secondreflecting surface forming two sides of a tunnel, said tunnel having afirst and a second aperture at the ends of said tunnel, means mountingsaid tunnel to allow light to enter said first aperture and reflect fromsaid reflecting surfaces and to project from said second aperture to anoptical surface spaced from said tunnel, and means establishing saidreflecting surfaces in a diverging relationship from one of saidapertures to reinforce the light intensity at the extremities of saidoptical surface.

Other objects and a fuller understanding of the invention may be had byreferring to the following description and claims, taken in conjunctionwith the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. I shows a top view of an opticalreflector system incorporating the present invention;

FIG. 2 is an isometric view of the preferred embodiment of the presentinvention;

FIG. 3 is an isometric view of a variation of the present invention;

FIG. 4 is a top view of the preferred embodiment shown in FIG. 2;

FIG. 5 is a diagram of a first diffuser means used in the inventionshown in FIGS. 2, 3, 4, 7 and 8;

FIG. 6 is a lenticular screen means which is used in the invention shownin FIGS. 2, 3, 4, 7 and 8;

FIG. 7 shows the invention incorporated into an optical projectionsystem;

FIG. is a modification of the optical projection system shown in FIG. 7;

FIG. 9 represents a character projected by the projection systems shownin FIG. 8 and illustrates the deficiencies of the prior art systemswhich are overcome by the present invention; and

FIG. 10 is a graph showing the intensity versus time of the light sourceused in FIGS. 7 and 8.

' DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. I shows an opticalreflector system incorporating the present invention. The system has afirst reflecting surface 11 and a second reflecting surface 12. In thisillustration, the reflecting surfaces are discrete and substantiallyflat forming two sides of a tunnel 13. The tunnel has a first aperturel4 and a second aperture 15 at the opposite ends of the tunnel. Thetunnel is mounted to allow light to enter the first aperture 14 from alight source I6 and to impinge on the first and second reflectingsurfaces 11 and 12. The reflections from the first and second reflectingsurfaces 11 and 12 project from the second aperture 15 to an opticalsurface il8 spaced from the tunnel. This optical surface can either be areal surface or an imaginary optical surface or plane used to aid theexplanation. FIG. 1 shows the first and second reflecfirigsurfaces 11and 12 in a diverging relationship from one of the apertures. In thiscase, the reflecting surfaces 11 and 12 are diverging from the firstaperture 14. The diverging relationship creates thevirtual image lightsources 16A and 163 to reinforce the light intensity at the extremities18A and 18B of the optical surface 18.

The drawing in FIG. 1 shows a matrix 25 located in proximity to thesecond aperture 15. The matrix 25 has a matrix window-ldwhigh allows thereflected rays from the reflecting surfaces 11 and 12 to project to theopfical surface 18. Since the matrix window 26 is a small aperturecompared to the second aperture 15, the diagram of the rays impingingupon the optical surface 18 is greatly simplified. A ray is coincidentwith the optical axis of the optical reflector system and impinges onthe optical surface 18 at 18C. The reflected rays 21 and 22 propagatingfrom the virtual image light sources 168 AND 16A, respectively, projectto the extremities 18B and 18A of the optical surface 18. In the absenceof the reflecting surfaces 11 and 12, the virtual image light sources16A and 1613 would be absent and the light intensity at the extremities18A and 1813 would be essentially zero. Thus, the presence of the firstand second reflecting surfaces 11 and 12 has created the virtual imagelight sources 16A and 168 which reinforce the intensity at theextremities of the optical surface 18. The light intensity on theoptical surface 18 is not uniform. This non-uniformity is caused by thefact that the rays 21 and 22 are less intense than the ray 20. The rays21 and 22 undergo a reflection from the reflecting surfaces 11 and 12and travel a longer distance before reaching the optical surface 18 thanthe ray 20. The brightest light intensity on the optical surface 18 willoccur at point 13C. Although the intensity at the extremities 112A and18B of the optical surface 18 is not as great as in the center 18C, theintensity is substantially greater than it would be if the first andsecond reflecting surfaces 11 and 12 were not present. If the matrix 25were removed, the angle of projection upon the optical surface 18 wouldbe increased and the ray pattern would become more complex. However, thephenomena of the virtual light sources reinforcing the extremities ofoptical surface 18 would still be present. The angle of divergence,dihedral angle, of the first and second reflecting surfaces determinesthe number and position of virtual light sources. As the reflectingsurfaces 11 and 12 are extended, the reflected rays undergo multiplereflections creating ad ditional virtual image light sources.

FIG. 2 is the preferred embodiment of the present invention. FIG. 2shows the first and a second reflecting surface 1 1 and 12, forming twosides of a diverging tun nel 13. The tunnel diverges from the firstaperture 14 toward the second aperture 15 at the opposite end of thetunnel. The light source 16 is located at the first aperture to allowlight to enter and to reflect from the surfaces 11 and 12. The reflectedlight from the reflecting surfaces project from the second aperture 15to an optical surface, not shown. Virtual images are formed by thediverging reflecting surfaces 11 and 12 in a manner similar to FIG. 1.

The illustration in FIG. 2 shows a first reference plane 41 and a secondreference plane 42. These reference planes are mutually perpendicular toone another. The reflecting surfaces 11 and 12 are each substantiallyperpendicular to the first reference plane 41 and are each facing thesecond reference plane 42. The reference planes are shown as finiteplanes for the sake of simplicity, but each reference plane extendsthrough the optical reflector system. The light source 16 has a lengthgreater than its width. This type of light source could be either afilament of an incandescent bulb or an electric arc, e.g. The length ofthe light source 16 shown in FIG. 2 is mounted in the first referenceplane 41.

The optical reflector system in F16. 2 illustrates diffuser means showngenerally as 30. The diffuser means diffuses light from the light source16 to produce a substantially uniform intensity on an optical surfacespaced from the reflector system. FIG. 2 also can be considered to becomposed of a plurality of diffuser means having a first diffuser means31, a second diffuser meand 32, and a third diffuser means 33. The firstdiffuser means 31 is in proximity to the first aperture 14 and diffuseslight in a direction substantially parallel to the first reference plane4-1. The first diffuser means is located in a strategic position todiffuse the unreflected light propagating from the light source 16. Thefirst diffuser means also diffuses some reflected light from one of thereflecting surfaces but the majority of the light diffused by the firstdiffuser means 31 is the direct radiation from light source 16. Thesecond diffuser means 32 is located within the tunnel and diffuses lightin a direction substantially parallel to the second reference plane 42,and the third diffuser means 33 is in proximity to the second aperture15 and diffuses light in the direction substantially parallel to thefirst reference plane 41. The first diffuser means 31 reduces theintensity of the direct rays passing from the light source 16 to theoptical surface as illustrated by ray 20 in FIG. 1. The second and thirddiffuser means work in combination with the first diffuser means toproduce a substantially uniform intensity on an optical surface spacedfrom the tunnel.

FIG. 3 shows a modification of the preferred embodiment shown in FIG. 2.FIG 3 illustrates a first and a second reflecting surface 11 and 12, afirst and second aperture 1 1 and 15 of the tunnel and first and secondmutually perpendicular reference planes 41 and 42. The reflectingsurfaces 11 and 12 are substantially perpendicular to the firstreference plane 41 and are each facing the second reference plane 42.The light source 16 has a length and a width in which the length thereofis mounted in the second reference plane 42. The illustration in FIG. 3also shows a first diffuser means 31, a second diffuser means 34 and athird diffuser means 35. The first diffuser means 31 is located inproximity to the first aperture 14 and diffuses unreflected light fromthe light source 16 in a direction substantially parallel to the firstreference plane 11. This diffuser reduces the intensity of theunreflected beam to a level commensurate with the intensity of thereflected beams as shown in FIG. 1. The second diffuser means 34 islocated within the tunnel and diffuses light in a directionsubstantially parallel to the first reference plane 41. The thirddiffuser means 35 is located in proximity to the second aperture 15 anddiffuses light in a direction substantially parallel to both the firstand second reference planes 4,1 and 42. Although the orientation of thelight sources and second and third diffuser means in the tunnels shownin FIGS. 2 and 3 are different, each tunnel produces a substantiallyuniform light intensity on an optical surface spaced from the tunnels.

FIG. 4 illustrates the top view of the preferred embodiment shown inFIG. 2. The optical reflector system has a first reflecting surface 11and a second reflecting surface 12 forming two sides of the tunnel 13.The tunnel has a first aperture 14 and a second aperture 15. The tunnel13 may be formed from two interfitting bases of cast metal, for example.The tunnel has a recess 44 to receive a gas flash lamp 43, the arc ofwhich is the light source 16. The recess 34 may be considered as a meansmounting the tunnel to allow light from the light source 16 to enter thefirst aperture 14 and reflect from the first and second reflectingsurfaces 11 and I2. The reflected light from the reflecting surfacesproject from the second aperture to an optical surface spaced from thetunnel which is not shown. The tunnel bases have lengthwise grooves 46to receive and hold the front surface mirrors as first and secondreflecting surfaces 11 and T2. The grooves 4 6 are thus a meansestablishing the surfaces 11 and T2 in a diverging relationship from thefirst aperture 14 to reinforce the intensity at the extremities of theoptical surface. The illustration in FIG. 4 also contains the first,second and third diffuser means 31, 32 and 33, which were previouslydescribed in the description of FIG. 2. The light source 16 is shown asan electric are such as an electric arc in a Xenon flash tube.

The dihedral angle formed by the reflecting surfaces and the placementof the first, second and third diffuser means 31, 32 and 33 determinethe distribution of the light intensity projected upon the opticalsurface. In the illustration shown in FIG. 4, the dihedral angle betweenthe reflecting surfaces is approximately 1 1".

FIG. 5 represents an example of a diffuser means 31 which can be usedfor the first diffuser means mentioned in FIGS. 2-4. The diffuser meansis composed of a transparent cylindrical tubing diffuser 48. The axis ofthe first diffuser 48 is mounted in the second reference plane 42 ofFIGS. 2 and 3. The diffuser diffuses light in a direction substantiallyperpendicular to the axis of the cylinder. Since the first diffuser ishollow, an optional neutral density filter shown as 49 can be insertedwithin the first diffuser 48 to reduce the intensity of the unreflectedbeams propagating from the light source.

FIG. 6 illustrates alenticular diffuser 53 which is suitable for use asthe second diffuser means 32, 34 and the third diffuser means 33 ofFIGS. 2-4. The diffuser is composed of a transparent material formed ina series of closely spaced adjacent half cylinders. The axes 54, 55 etc.of each of the half cylinders are parallel and lie in the fiat backsurface of the diffuser. Parallel light entering the flat back surfaceof the diffuser is diffused in a direction substantially perpendicularto the axes of the half cylinders. Each half cylinder of the diffusermeans acts as an individual light source to provide the opticalreflector system with the proper balance of directed and diffused lightto enable a substantially uniform intensity to be projected upon anoptical surface spaced from the reflector system. The third diffusermeans 35 of FIG. 3 is composed of two diffuser means as shown in FIG. 6having the axes of one diffuser means perpendicular to the axes of theother diffuser means. An alternative arrangement is a single diffusermeans having half cylinders scribed in two perpendicular directions.

The optical reflector system described in FIGS. 1-6 can be used in anoptical projection system. One such application, shown in FIG. 1,illustrates a rudimentary photo-composition or photo-type settingapparatus. The optical reflector system which comprises a portion of theoptical projection system has already been described. The projectionsystem operates when a matrix character appears in the matrix window 26.This 'matrix character will be projected within the included angle fromthe matrix window to the extremities of 18A, 18B of the optical surface18. The optical surface would normally be a photo-sensitive materialsensitiue to the projected character from the matrix window 26. Amovable lens 23 focuses the projected character from the matrix windowto the optical surface 18. A mask (not shown) is located about theperimeter of the lens 23 to block extraneous light from reaching theoptical surface 18. Only light passing through the lens 23 will impingeupon the opticalsurface 13. The movement of the lens 23 in a lineardirection as shown by the arrows enables a character located in thematrix window 26 to be projected at any point along the optical surface18. When the lens 23 is in one of the extreme directions of scan shownas positions 23A and 238, a central beam from the matrix window does notpass through the lens parallel to the optical axis of the lens. Thisnon-parallel incident ray causes a decrease in the light transmittanceof the lens 23 in relationship to the fourth power of the cosine of theangle between the axis of the lens and the incident rays from the matrixwindow. This angle is designaged 6i and 62 in FIG. 1.

The optical reflector system disclosed in this invention is able tocompensate for this fourth power decrease in light transmittance of lens23. The first diffuser means 31 shown in FIGS. 2-5 diffuses and reducesthe intensity of the central beam shown as 20 in FIG. I. In addition,the first and second reflecting surfaces II and 12 in FIG. I reinforcethe light intensity of the extremities 18A, 18B of the optical surface18. With the proper selection of the first diffuser means, and thedihedral angle between the first and second reflecting surfaces Ill and12, the decrease in the light transmittance of the lens 23 in positions23A and 2313 can be compensated producing a uniform intensity throughoutthe projected angle of scan on the optical surface 18. A uniformintensity on an optical surface such as a photo-sensitive surface forphoto-type setting or photo-composition is essential for proper imagequality.

FIG. 7 shows an optical projection system incorporating the opticalreflector system in accordance with this invention. The opti alreflector system shown generally as 56 has a first and econd reflectingsurface II and I2 diverging from a light source 16. The reflector system56 has a first diffuser 31, a second diffuser 32 and a third diffuser 33as described in FIG. 2.

The light source 16 is of the type capable of producing a short durationpulse of light on the order of several microseconds. The power source 53furnishes power and triggers the light pulsefThe optical projectionsystem has a matrix 25 which rotates about a shaft 60 driven by a motor62. The matrix is opaque with the exception of matrix windows 26 inwhich the characters are located. As the matrix wheel rotates, thecharacters to be projected rotate sequentially. A light beam projectingfrom the matrix window 26 strikes a system of two mirrors 71A and 72Awhich are movable by a scanner 64 along a line indicated by the arrows.When the mirror pair is in the HA and 72A position, a beam 22propagating from the matrix window 26 will pass through the lens 23 tothe extremity 13A of the optical surface 13. This beam enters the lens23 nonparallel to the axis of lens forming an angle 61. When the scanner64 moves the mirror pair into the 718 and 72B position, a beam 21propagating from the matrix window 26 passes through the lens 23 to theother extremity I88 of the optical surface 18. This-beam enters the lens23 at an angle 62 with respect to the optical axis of the lens 23. Themovement of the mirror pair by the scanner means 64 determines theposition of the projection of the character in the matrix window 26. Amask 67 with an aperture for the lens ensures that only the beamspassing through the lens 23 will reach the optical surface 18. Thesynchronization between the rotation of the matrix 25 and the pulse oflight by the light source 16 determines the character projected. Withthe proper dihedral angle between the reflecting surfaces Ill and I2,and the proper first diffuser means 31, the optical reflector system 56compensates for the decrease in transmittance of the lens 23 at theextremities 113A and I88 of the scan to project a uniform intensitycharacter irrespective of the position along the optical surface I8.

FIG. f3 shows another view of an optical projection system similar tothe type shown in FIG. ll. An optical reflector system 56 identical tothe type shown in FIGS. 2, 4, 7 is mounted to a light source 16 whichprojects light through a matrix window 26 and a lens 23 to an opticalsurface 18. The matrix 25 is moving along a line shown by the arrow. Thelens 23 is movable along a line determined by the double headed arrow toscan along the optical surface 18.

Since the matrix 25 is rapidly moving, the pulse time of the lightsource I6 must be short enough to stroboscopically stop, the matrixwindow 26 so that the projected image 75 will not be blurred. FIG. 9shows an example of the projected image 75 when the pulse length of thelight source 16 is too long compared to the speed of the matrix 25. Theimage is blurred in the direction of the movement of the matrix 25. Ifthe letters have serifs '78, these especially can be blurred by therapid movement of the matrix.

The prior art systems which have tried to use a short duration flashtube to scan a line field such as that of the optical surface I8, havebeen unable to produce a unform intensity along the line field. Theprior art systems that have been able to obtain a uniform intensityalong the line field did this at the expense of increasing the arclength of the light source. The duration of the pulse in a flash tube isproportional to the arc length. Therefore, by tripling the arc length ofthe flash tube, a uniform intensity was achieved across the line fieldbut the flash was unable to stroboscopically stop the matrix character.The end result was a blurred character as shown in FIG. 9. Some priorart systems use a plurality of flash tubes to effectively extend the arclength without increasing the arc duration. FIG. I shows by a curve 80that the pulse time of the prior art is long relative to the presentinvention which short pulse time is shown in curve 81, yet each systemhas the same effective arc length.

FIGS. 7 and 8 illustrate a method of projecting characters from thematrix 25 by the light source 16 and the lens 23 upon differentpositions of the optical surface 18 with substantially uniformintensity. The method of projection contains four steps. The first stepincludes moving the matrix 25 to index the characters contained on thematrix. Moving the matrix includes rotating the matrix wheel as shown inFIG. 7 or linearly moving the matrix as shown in FIG. 3.

The second step in the method of projecting characters is pulsing thelight source 16 in synchronization with the matrix to stroboscopicallyproject a selected character through the lens 23 to the optical surface18. Pulsing the light includes igniting a flash tube such as a Xenonflash tube. Concomitantly, pulsing the light includes directing lightand reflecting light from the reflecting surfaces II and I2 from thelight source I6 to the matrix 25. The method shown in FIGS. 7 and 8 alsoincludes attenuating the directed light from the light source In bymeans of the first diffuser means 3i. The method also illustratesdiffusing light propagating from the light source I6 to the matrix 25 bythe second and third diffuser means 32 and 33.

FIGS. '7 and 8 illustrate the third step of varying the position of theprojected character on the optical surface ilfl. This variation producesa variation in the angle formed between the projected beam and theoptical axis of the lens 23. In FIG. '7, varying the position of theprojected character is accomplished by moving the reflecting surfaces71A, 72A located between the matrix 25 and the optical surface I8. 8illustrates that the varying of the position of the projected charactercan be accomplished by moving the lens 23.

The fourth step in the method of projecting characters is reinforcingthe light which is projected through the matrix to compensate for thevariation in light transmittance of the lens 23 produced by thevariation in the angle between the projected beam and the optical axisof the lens 23. Reinforcing the light includes reflecting light from thelight source I6 which results in creating virtual images to extend theeffective length of the light source 16. The method of reflecting lightfrom the optical reflector system 56 includes reflecting light at anangle relative to the optical axis 20 shown in FIG. l which angle isdifferent from the angle of the incident light relative to the opticalaxis 20. This phenomena results from the fact that the first and secondreflecting surfaces 11 and 12 are diverging from one of the apertures Mand I5.

In a system actually constructed by the inventor, the optical reflectorsystem contained first surface glass reflecting surfaces which wereapproximately an inch long and one-half inch wide. The reflectingsurfaces had a dihedral angle of approximately 1 1 and was able tocompensate for a lens system and produce a uniform intensity on anoptical surface within a projected angle of approximately 20. The lightsource was a Xenon flash tube having an arc length of flve-sixteenths ofan inch which was effectively increased to a one inch arc. The durationof the Xenon pulse still remained at approximately two microseconds andwas able to stroboscopically stop a rotating matrix wheel as shown inFIG. 7. The variation in intensity on the optical surface between theextremities was less than Spercent and well within the requirements forthe photo-type setting and photo-composition arts. The system wascompact and was able to be produced at a minimum cost. The reflectorsystem was able to be placed within machines during the manufacturingprocess without special adjustments, and not requiring any speciallytrained personnel.

A t gh the optical reflector system can be ad- 5. An optical reflectorsystem as set forth in claim 2, justed to compensate for other opticalcomponents, the wherein said second and third diffuser means includessystem can also be used to produce a desired distribulenticular screenmeans. tion in light intensity on the optical screen. if an appli- 6. Anoptical reflector system as set forth in claim 2,

cation required an increase in intensity at the extremi- 5 wherein saidfirst diffuser means includes a first diffuser ties of the opticalsurface, this could be accomplished and filter means.

by the disclosed invention. Similarly, the light source 7. An opticalreflector system as Set forth in Claim used in conjunction with theoptical reflector system is wherein said first diffuser includestransparent tube not limited to a light source having a length and awidth meansbut could also be used with a point light source. l 8. Anoptical projection system, comprising in com- The present-discl'osiii'eincludes that contained in the bination, appended claims, as well asthat of the foregoing a light Source, description. Although thisinvention has been an image Surface, described in its preferred formwith a certain degree of l a pl rali y of reflecting surfaces,particularity, it is understood that the present disclomeans t ng saidsurfaces diverging from said sure of the preferred form has been madeonly by way light SOUX'CB 10 project light from said light source ofexample and that numerous changes in the details of to Said imageSurfafifi, construction and the combination and arrangement of means-Establishing an Object beiwesn Said light parts may be resorted towithout departing from the Source and Said image Surfacg to P j imagespirit and the scope of the invention as hereinafter Ofsaid Objectsaidimage Surface l i d, means varying the relative position of saidimage and What is claimed is; said image surface along a first path, 1.An optical reflector system comprising, in comand said light source andsaid reflecting surfaces bination, being fixed relative to said imagesurface along a first and a second reflecting surface forming two Saidfirst path.

id f t n l, 9. An optical projection system as set forth in claim id flti Surfaces are h b t ti ll 8, wherein said reflecting surfaces aresubstantially flat. ndicular to a first refe plane d are h 10. Anoptical projection system as set forth in claim facing a secondreference plane where said 3, including diffuser means between saidlight source reference planes are mutually perpendicular, and said imagesurface resulting in said image being said tunnel having a first and asecond aperture at the substantially uniform in intensity regardless ofthe posiends of said tunnel, tion of said image on said image surface.means mounting said tunnel to allow light to enter 11. An opticalprojection system as set forth in claim id fi t rtur and r flect fromsaid fl ti 8, wherein said relative position varying means includessurfaces and to project from said second aperture Scanning meansto an il Surface spaced f id t l, 12. An optical projection system as set forthin claim means establishing said reflecting surfaces in a 8, whereinsaid image surface is a substantially linear diverging relationship fromone of said apertures field having a long length relative to the widththereof.

to reinforce the light intensity at the extremities of An opticalProjection y m as Set forth in claim id ti l rf 8, wherein said lightsource includes a short duration and a plurality of diffuser means todiffuse light in electric directions substantially parallel to saidreference said duration of said electric arc being substantially planesproducing a substantially uniform intensity pr portional to the arclength thereof, on said optical surface. said means estabiishing anobject includes a rapidly 2. An optical reflector system as set forth inclaim 1, high moving character matrix means wherein a wherein saidplurality of diffuser means includes a first, given character isstroboscopically projected on second, and third diffuser means, saidimage surface,

said first diffuser means being in proximity to said and said meansmounting said surfaces produces a first aperture to diffuse unreflectedlight in a plurality of virtual image sources which optically directionsubstantially parallel to said first increase said arc length to produceincreased light reference plane, output without an increase in arcduration.

a second diffuser means being within said tunnel to M. The method ofprojecting characters from a diffuse light in a direction substantiallyparallel to matrix by a light source and a lens upon different posia oneof said reference planes, tions of an optical surface with substantiallyuniform inand said third diffuser means being in proximity to tensitycomprising the following steps;

said second aperture to diffuse light in a direction moving the matrixto index the characters thereof, substantially parallel to the other ofsaid reference pulsing the light source in synchronization with theplanes. matrix to stroboscopically project a selected 3. An opticalreflector system as set forth in claim 2, character through the lens tothe optical surface, wherein said one of said reference planes is saidsecond varying the position of the projected character on the referenceplane. optical surface producing a variation in an angle 4. An-opticalreflector system as set forth in claim 2, formed between the projectedbeam and the optiwherein said third diffuser means diffuses light in acal axis of the lens, direction substantially parallel to said first andsecond and reinforcing the light to compensate for the variareferenceplanes. tion in light transmittance of the lens produced by c l I I, C

lli

the variation of the angle between the projected beam and the opticalaxis of the lens.

15. The method as set forth in claim 1 wherein moving the matrixincludes rotating a matrix wheel.

16. The method as set forth in claim i4, wherein pulsing the lightincludes igniting a flash tube.

17. The method as set forth in claim 14, wherein pulsing the lightincludes directing light and reflecting light from the light source tothe matrix.

58. The method as set forth in claim Y7, including attenuating thedirected light.

19. The method as set forth in claim 14, including diffusing lightpropagating from the light source to the matrix.

2!}. The method as set forth in claim M, wherein varying the positionincludes moving a reflecting surface between the matrix and the opticalsurface.

21. The method as set forth in claim 1 wherein reinforcing the light isby light from the light source.

22. The method as set forth in claim 14, wherein reinforcing the lightincludes creating virtual images of the light source to extend theeffective length of the light source.

23. The method as set forth in claim 14, wherein reinforcing the lightincludes reflecting light from the light source.

24. The method as set forth in claim 14, wherein reinforcing the lightincludes reflecting light at an angle said tunnel having a first and asecond aperture at the ends of said tunnel,

means mounting said tunnel to allow light to enter said first apertureand reflect from said reflecting surfaces and to project from saidsecond aperture to an optical surface spaced from said tunnel, 7

lens means between said tunnel and said optical surface,

means establishing said reflecting surfaces in a diverging relationshipfrom one of said apertures to reinforce the light intensity at theextremities of said optical surface;

to compensate for the falloff of said lens means due to light enteringnon-parallel to the optical axis of said lens means,

and diffuser means between said tunnel and said lens means producing asubstantially uniform intensity on intensity on said optical surface.

1. An optical reflector system comprising, in combination, a first and asecond reflecting surface forming two sides of a tunnel, said reflectingsurfaces are each substantially perpendicular to a first reference planeand are each facing a second reference plane where said reference planesare mutually perpendicular, said tunnel having a first and a secondaperture at the ends of said tunnel, means mounting said tunnel to allowlight to enter said first aperture and reflect from said reflectingsurfaces and to project from said second aperture to an optical surfacespaced from said tunnel, means establishing said reflecting surfaces ina diverging relationship from one of said apertures to reinforce thelight intensity at the extremities of said optical surface, and aplurality of diffuser means to diffuse light in directions substantiallyparallel to said reference planes producing a substantially uniformintensity on said optical surface.
 2. An optical reflector system as setforth in claim 1, wherein said plurality of diffuser means includes afirst, second, and third diffuser means, said first diffuser means beingin proximity to said first aperture to diffuse unreflected light in adirection substantially parallel to said first reference plane, a seconddiffuser means being within said tunnel to diffuse light in a directionsubstantially parallel to one of said reference planes, and said thirddiffuser means being in proximity to said second aperture to diffuselight in a direction substantially parallel to the other of saidreference planes.
 3. An optical reflector system as set forth in claim2, wherein said one of said reference planes is said second referenceplane.
 4. An optical reflector system as set forth in claim 2, whereinsaid third diffuser means diffuses light in a direction substantiallyparallel to said first and second reference planes.
 5. An opticalreflector system as set forth in claim 2, wherein said second and thirddiffuser means includes lenticular screen means.
 6. An optical reflectorsystem as set forth in claim 2, wherein said first diffuser meansincludes a first diffuser and filter means.
 7. An optical reflectorsystem as set forth in claim 6, wherein said first diffuser includestransparent tube means.
 8. An optical projection system, comprising incombinatiOn, a light source, an image surface, a plurality of reflectingsurfaces, means mounting said surfaces diverging from said light sourceto project light from said light source to said image surface, meansestablishing an object between said light source and said image surfaceto project an image of said object on said image surface, means varyingthe relative position of said image and said image surface along a firstpath, and said light source and said reflecting surfaces being fixedrelative to said image surface along said first path.
 9. An opticalprojection system as set forth in claim 8, wherein said reflectingsurfaces are substantially flat.
 10. An optical projection system as setforth in claim 8, including diffuser means between said light source andsaid image surface resulting in said image being substantially uniformin intensity regardless of the position of said image on said imagesurface.
 11. An optical projection system as set forth in claim 8,wherein said relative position varying means includes scanning means.12. An optical projection system as set forth in claim 8, wherein saidimage surface is a substantially linear field having a long lengthrelative to the width thereof.
 13. An optical projection system as setforth in claim 8, wherein said light source includes a short durationelectric arc, said duration of said electric arc being substantiallyproportional to the arc length thereof, said means establishing anobject includes a rapidly high moving character matrix means wherein agiven character is stroboscopically projected on said image surface, andsaid means mounting said surfaces produces a plurality of virtual imagesources which optically increase said arc length to produce increasedlight output without an increase in arc duration.
 14. The method ofprojecting characters from a matrix by a light source and a lens upondifferent positions of an optical surface with substantially uniformintensity comprising the following steps; moving the matrix to index thecharacters thereof, pulsing the light source in synchronization with thematrix to stroboscopically project a selected character through the lensto the optical surface, varying the position of the projected characteron the optical surface producing a variation in an angle formed betweenthe projected beam and the optical axis of the lens, and reinforcing thelight to compensate for the variation in light transmittance of the lensproduced by the variation of the angle between the projected beam andthe optical axis of the lens.
 15. The method as set forth in claim 14,wherein moving the matrix includes rotating a matrix wheel.
 16. Themethod as set forth in claim 14, wherein pulsing the light includesigniting a flash tube.
 17. The method as set forth in claim 14, whereinpulsing the light includes directing light and reflecting light from thelight source to the matrix.
 18. The method as set forth in claim 17,including attenuating the directed light.
 19. The method as set forth inclaim 14, including diffusing light propagating from the light source tothe matrix.
 20. The method as set forth in claim 14, wherein varying theposition includes moving a reflecting surface between the matrix and theoptical surface.
 21. The method as set forth in claim 14, whereinreinforcing the light is by light from the light source.
 22. The methodas set forth in claim 14, wherein reinforcing the light includescreating virtual images of the light source to extend the effectivelength of the light source.
 23. The method as set forth in claim 14,wherein reinforcing the light includes reflecting light from the lightsource.
 24. The method as set forth in claim 14, wherein reinforcing thelight includes reflecting light at an angle relative to an optical axiswhich angle is different from the angle of the incident light relativeto the optical axis and wherein the optical axis interseCts the lightsource and the matrix.
 25. An optical reflector system comprising, incombination, a first and a second reflecting surface forming two sidesof a tunnel, said tunnel having a first and a second aperture at theends of said tunnel, means mounting said tunnel to allow light to entersaid first aperture and reflect from said reflecting surfaces and toproject from said second aperture to an optical surface spaced from saidtunnel, lens means between said tunnel and said optical surface, meansestablishing said reflecting surfaces in a diverging relationship fromone of said apertures to reinforce the light intensity at theextremities of said optical surface; to compensate for the falloff ofsaid lens means due to light entering non-parallel to the optical axisof said lens means, and diffuser means between said tunnel and said lensmeans producing a substantially uniform intensity on intensity on saidoptical surface.